The NATO Treaty, officially known as the North Atlantic Treaty, was signed on April 4, 1949. It established the North Atlantic Treaty Organization, a military alliance aimed at ensuring collective defense among its member countries. The treaty states that an armed attack against one member is considered an attack against all, promoting mutual support and security. The NATO Treaty was created in response to the growing tensions of the Cold War and the threat posed by the Soviet Union. Over the years, NATO has expanded to include 30 member countries, adapting to new security challenges while maintaining its core principle of collective defense.